Examples

Demonstration programs for VIGRA's usage.

Click on the hyperlinks to view the commented source code for the demos. Most examples can be applied to both gray-scale and RGB images. See Installation for instructions on how these programs can be compiled. For convenience, the directory contains the test images lenna_gray.gif and lenna_color.gif.

• Convert an image file into another file type: convert.cxx
  Usage: example_convert infile outfile

• Read an image file and write out a subimage: subimage.cxx
  Usage: example_subimage infile outfile

• Invert an image file (create a negative) using the function transformImage(): invert.cxx
  Usage: example_invert infile outfile

• Invert an image file (create a negative) by coding the loop explicitly: invert_explicitly.cxx
  Usage: example_invert_explicitly infile outfile

• Resize an image using resizeImageSplineInterpolation(): resize.cxx
  Usage: example_resize infile outfile

• Smooth an image using Recursive convolution functions functions: smooth.cxx
  Usage: example_smooth infile outfile

• Find the gray value profile along the image diagonal by means of a vigra::LineIterator : profile.cxx
  Usage: example_profile infile, generates profile.gif

• Create series of slices through different color spaces.: palette.cxx
  Usage: example_palette lab, generates lab_*.gif (44 images)

• Reduce image size by mean of a Gaussian pyramid: pyramid.cxx
  Usage: example_pyramid infile outfile

• Find edges by means of a differenceOfExponentialEdgeImage(): edge.cxx
  Usage: example_edge infile outfile

• Segment image by means of the watershed algorithm, using seededRegionGrowing(): watershed.cxx
  Usage: example_watershed infile outfile

• Generate a Voronoi diagram, using distanceTransform() and seededRegionGrowing(): voronoi.cxx
  Usage: example_voronoi, generates: distances.gif (Euclidean distance transform) and voronoi.gif (Voronoi diagram)

• Measure boundary and corner strengths with the boundaryTensor(): boundarytensor.cxx
  Usage: boundarytensor infile, creates boundarystrength.tif and cornerstrength.tif

• Total Variation (TV) Regularization total_variation.cxx
  Usage: example_total_variation parameterfile (cf. example parameter files *.par for standard TV regularization, anisotropic and second order TV)

• Non-negative least-squares regression nnlsq.cxx
  Usage: example_nnlsq (no parameters - example data are defined in nnlsq.cxx)